This is the second-oldest item I've discovered in the bowels of my office - the oldest being a commencement program from 1884 - but this item is interesting as well. It's a 1919 calendar from Turlock Mercantile Co. in Turlock, California. Besides its age, I thought the overall design of the calendar was interesting. Although a little ripped up and some water damage, the calendar portion looks like it was never used.
The Turlock Mercantile Building as it looked in 2014, photo courtesy of Google Earth.
An article in the Turlock Journal notes that paranormal investigations were done at Turlock Mercantile building in 2008. Numerous reports were made over the years of strange noises and ghost sightings, so some amateur investigators decided to look into it, and got strange results themselves - the article says it better than I could: "[They] got more than they bargained for when rattling noises began and the front door alarm went off right in front them. Even more spooky were the sounds of footsteps and a six-digit phone number being dialed the recorder picked up and the unexplained ending of the tape, even though the reels were still turning."
At that point, they brought in the professionals who did their own investigation and concluded that the ghost of the building's founder, Horace Crane, was among many that still called the building "home." If you want an interesting read, consult the original story at http://www.turlockjournal.com/archives/6309/.